JPH0747267Y2 - Soundproof structure for automobile floor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a soundproof structure for an automobile floor in which a hot-melt sheet is welded to the surface of the floor.

(Prior Art) Conventionally, for example, the soundproof structure is disclosed in Japanese Utility Model Laid-Open No. 55-102676.

Explaining this, the floor has a lower step portion that extends substantially horizontally, a vertical wall portion that extends upward from one end edge of the lower step portion, and a direction away from the lower step portion in plan view from the upper end edge of the vertical wall portion. And an upper step portion that extends substantially horizontally toward. Further, the joint between the lower step portion and the vertical wall portion extends substantially horizontally, and the hot melt sheet is welded to the surface of the floor.

Further, according to the above configuration, when the floor vibrates during traveling and the floor is about to generate noise, the heat-melting sheet absorbs the noise of the floor and exhibits a soundproof effect.

(Problems to be solved by the invention) By the way, the heat-melting sheet in the above-mentioned conventional structure is composed of a plurality of heat-melting sheets of a certain size, and a gap is formed between the end portions of the adjacent heat-melting sheets. There is. Therefore, the noise of the floor may not be sufficiently absorbed by the heat-melted sheet.

Therefore, it is conceivable to join the ends of the adjacent heat-melted sheets to each other in the direction along the surface of the floor and weld them to the surface of the floor. However, since the dimensional accuracy of the hot-melt sheet before welding is generally rough, the above-mentioned welding operation is complicated.

Therefore, it is conceivable that the end portions of adjacent heat-melting sheets are overlapped and welded to each other so that the above-mentioned gap does not occur. However, when this overlap portion is formed on the upper surface of the floor, the heat-melting sheet on the floor is formed. The occupant's comfort against the surface of the vehicle may be reduced.

(Purpose of the Invention) The present invention was made by paying attention to the above-mentioned circumstances, and the heat-melting sheet is more entirely welded to the surface of the floor to improve the soundproof effect, and the welding work is performed. It is intended to make it possible to easily perform, and to maintain a good feeling of stepping on the surface side of the floor.

(Structure of the Invention) A feature of the present invention for achieving the above-mentioned object is that a heat-melted sheet is welded to a lower sheet and a vertical sheet is welded to a surface of a vertical wall. And a vertical wall sheet and an upper sheet that is welded to each surface of the upper step portion, and the edges of the lower sheet and the vertical wall sheet on the side of the joint portion are separated from each other with the joint portion interposed therebetween. Along with the same as above, the point is that they are substantially parallel to each other.

(Operation) The operation of the above configuration is as follows.

As shown in FIG. 3 and FIG. 4, the surface of the floor 1 is entirely covered with the lower sheet 8a, the vertical wall sheet 8b, and the upper sheet 9, and the vertical wall sheet 8b and the upper sheet 9 are also covered.
And are superposed on the surface side of the vertical wall portion 3. Therefore, noise due to the vibration of the floor 1 is more surely absorbed.

Further, since at least a part of each of the vertical wall sheet 8b and the upper sheet 9 is superposed, an error in arrangement at the time of welding the vertical wall sheet 8b and the upper sheet 9 and each dimension at the overlapping portion. The error can be absorbed.

Further, since the overlapping portion of the vertical wall sheet 8b and the upper sheet 9 is located on the surface of the vertical wall portion 3, each upper surface side of the lower step portion 2 and the upper step portion 4 which are the treads of the occupant are flat. Keep in shape.

(Embodiment) An embodiment of the present invention will be described below with reference to the drawings.

In FIGS. 3 and 4, 1 is a sheet metal floor of an automobile, and an arrow Fr in FIG. 1 indicates the front of the vehicle body in the traveling direction.

The floor 1 includes a lower step portion 2 which is a front floor extending substantially horizontally, a vertical wall portion 3 which extends upward from a rear end edge which is one end edge of the lower step portion 2, and an upper end edge of the vertical wall portion 3. There is an upper step portion 4 which is a rear floor extending substantially horizontally toward the rear which is a direction away from the lower step portion 2 in a plan view, and these are bent and formed by pressing one plate material.

The upper step portion 4 is one step higher than the lower step portion 2, and the joint portion 11 between the lower step portion 2 and the vertical wall portion 3 and the joint portion 10 between the vertical wall portion 3 and the upper step portion 4 are It extends substantially horizontally in the width direction and has sufficient rigidity.

Although not shown, a seat is attached on the lower stage 2 and a fuel tank is provided below the upper stage 4. A floor tunnel 5 is formed at the center of the lower portion 2 in the vehicle width direction.

A hot melt sheet 7 is welded to the surface of the floor 1. The hot-melt sheet 7 is made of asphalt and has a certain degree of hardness at room temperature.

The hot-melt sheet 7 includes a lower sheet 8a welded to the surface of the lower portion 2, a vertical wall sheet 8b welded to the surface of the vertical wall portion 3 with the same material as the lower sheet 8a, and the vertical wall. A sheet 8b and an upper sheet 9 welded to each surface of the upper portion 4 are provided, and the lower sheet 8a and the vertical wall sheet 8b are provided.
The edges 14, 14 on the side of the joint 11 in
They are separated from each other by sandwiching 1 therebetween, and are substantially parallel to each other along the same joint portion 11.

As shown in FIG. 3 and FIG. 4, the surface of the floor 1 is entirely covered with the lower sheet 8a, the vertical wall sheet 8b, and the upper sheet 9, and the vertical wall sheet 8b and the upper sheet 9 are also covered.
And are superposed on the surface side of the vertical wall portion 3. Therefore, noise due to the vibration of the floor 1 is more surely absorbed.

Further, at least a part of each of the vertical wall sheet 8b and the upper sheet 9 is overlapped, and there is an error in arrangement when welding the vertical wall sheet 8b and the upper sheet 9 at each overlapping portion, and each dimensional error. Be absorbed.

Further, since the overlapping portion of the vertical wall sheet 8b and the upper sheet 9 is located on the surface of the vertical wall portion 3, each upper surface side of the lower step portion 2 and the upper step portion 4 which are the treads of the occupant are flat. It is kept in shape.

It should be noted that the surface of the joint portion 11 is a corner portion, and welding work to the joint portion 11 is difficult. So this joint
In 11, the lower sheet 8a and the vertical wall sheet 8b are separated from the edges 14 and 14 to avoid welding to the joint 11, but the edges 14 and 14 sandwich the joint 11. Are substantially parallel to each other, and the joint portion 11 is a portion in which the lower step portion 2 and the vertical wall portion 3 are joined substantially in the horizontal direction and the vertical direction and has sufficient rigidity to prevent vibration. This is a part that is unlikely to occur. Therefore, as described above, even if the edges of the lower sheet 8a and the vertical wall sheet 8b are separated from each other, the improvement of the soundproofing effect is not hindered.

In FIG. 1 and FIG. 2, when the heat-melting sheet 7 is to be welded to the surface of the floor 1, a lower sheet 8 in which a lower sheet 8a and a vertical wall sheet 8b are integrated is prepared. A fracture promoting portion 12 having a large number of slits arranged in a line is formed substantially linearly on the boundary line between the lower sheet 8a and the vertical wall sheet 8b in the sheet 8.

Then, as shown by the solid line in FIG.
The lower sheet 8a side of the lower sheet 8 is superposed on the surface of the lower step portion 2 so that the upper surface of the lower sheet 8 is opposed to the joint portion 11, while the edge of the vertical wall sheet 8b side is a midway portion in the vertical direction of the surface of the vertical wall portion 3. Lean against.

In addition, one end side 9a of the flat upper sheet 9 is attached to the upper step portion 4
On the other side of the upper sheet 9 while being superposed on the surface of
9b is made to project toward the lower step 2 side from the edge of the upper step 4 on the vertical wall 3 side.

In the above case, the atmosphere is at room temperature, and the lower sheet 8 and the upper sheet 9 have a certain degree of rigidity.
A space 13 having a triangular cross section is formed between the vertical wall sheet 8b side of the lower sheet 8 and the joint portion 11, and the upper sheet 9
The other end side 9b keeps the shape protruding forward.

From the above state, the lower sheet 8 and the upper sheet 9 are heated in a drying furnace. Then, as shown by the phantom line in FIG. 1 and FIG. 2, the lower sheet 8 begins to melt, and the portion of the lower sheet 8 corresponding to the above-mentioned joint portion 11 moves toward the space 13 by its own weight. While bending, it fits in the rear portion of the lower step portion 2 and slides downward on the surface of the vertical wall portion 3. And the lower sheet 8 which is in contact with the surface of the floor 1
Parts of the upper seat 9 start to be welded to the floor 1.

Further, when the lower sheet 8 and the upper sheet 9 are melted, the portion of the lower sheet 8 corresponding to the joint portion 11 is bent so as to expand toward the space 13, and at this time, the joint portion is the same.
One of the portions of the lower sheet 8 corresponding to 11 becomes thin and tries to break.

However, since the fracture promoting portion 12 is formed in this portion, the fracture promoting portion 12 fractures earlier than other portions as shown in FIGS. 8a
Then, the vertical wall sheet 8b is adapted to be welded to the respective surfaces of the lower step portion 2 and the vertical wall portion 3 by fitting.

Since the fracture promoting portion 12 corresponds to the joint portion 11, the fracture by the fracture promoting portion 12 coincides with the joint portion 11, as shown in FIGS. 3 and 4 above. That is, the lower sheet, which is both the breaking edges of the lower sheet 8.
The edges 14 and 14 of the 8a and the vertical wall sheet 8b are separated from each other with the joint portion 11 interposed therebetween, and the edges 14 and 14 of the lower sheet 8a and the vertical wall sheet 8b are along the joint portion 11. Are almost parallel to each other.

On the other hand, the upper sheet 9 is also softened, and the other end side 9b is bent downward as shown by the phantom line in FIG. 1, and the other end side 9b is welded to the vertical wall portion 3 and the vertical wall sheet 8b. Is welded to the surface of the.

As a result, the surface of the floor 1 is in the state shown in FIGS. 3 and 4 described above.

Then, as described above, the welding operation of the hot-melt sheet 7 can be obtained by setting the lower sheet 8 provided with the breakage promoting portion 12 and the upper sheet 9 at predetermined positions and heating them. Therefore, this work can be easily performed.

Note that, although the above is based on the illustrated example, the breakage promoting portion 12 is, instead of the plurality of slits, a long groove formed on at least one of the front and back surfaces of the heat-melting sheet 7, or a plurality of short grooves or the like. Good.

(Effect of the Invention) According to the present invention, the heat-melting sheet has a lower sheet welded to the surface of the lower portion, a vertical wall sheet welded to the surface of the vertical wall portion, the vertical wall sheet and the upper portion. Of the lower sheet and the vertical wall sheet, the edges of the lower sheet and the vertical wall sheet on the joint side are separated from each other across the joint and are substantially parallel to each other along the joint. Therefore, the following effects are obtained.

That is, the surface of the floor is entirely covered with the lower sheet, the vertical wall sheet, and the upper sheet, and the vertical wall sheet and the upper sheet are superposed on the surface side of the vertical wall portion. Therefore, the noise due to the vibration of the floor is more surely absorbed.

Further, since at least a part of each of the vertical wall sheet and the upper sheet is overlapped, an error in the arrangement when the vertical wall sheet and the upper sheet are welded at this overlapping portion,
Each dimensional error can be absorbed.

Therefore, since the welding work is not required to be accurate, the work can be easily performed.

Furthermore, since the overlapping portion of the vertical wall sheet and the upper sheet is located on the surface of the vertical wall portion, each upper surface side of the lower step portion and the upper step portion, which is the tread surface of the occupant, is kept flat, Therefore, the comfort of stepping on the front surface side of the floor can be maintained well.

The surface of the joint is a corner, and welding work to this joint is difficult. Therefore, at this joint, by welding the edges of the lower sheet and the vertical wall sheet away from each other, welding to the joint is avoided, but the edges are positioned substantially parallel to each other with the joint interposed therebetween. And, each of the joints is a portion in which the lower step portion and the vertical wall portion are joined from the substantially horizontal direction and the vertical direction, and has sufficient rigidity,
This is the part where vibration is unlikely to occur. Therefore, even if the edges of the lower sheet and the vertical wall sheet are separated from each other as described above, the improvement of the soundproofing effect is not hindered.

[Brief description of drawings]

FIG. 1 shows an embodiment of the present invention, FIG. 1 is a side sectional view, FIG. 2 is a perspective view of a broken line shown in FIG. 1, and FIG.
FIG. 4 is a perspective view of what corresponds to FIG. 3, and FIG. 1 ... Floor, 2 ... Lower part, 3 ... Vertical wall part, 4 ... Upper part, 7 ... Thermal melting sheet, 8 ... Lower sheet, 8a.
Lower sheet, 8b …… vertical wall sheet, 9 …… upper sheet, 9a
...... One end side, 9b ...... Other end side, 10 ...... Joined portion, 11 ...... Joined portion, 12 ...... Fracture promoting portion, 13 ...... Space, 14 ...... End edge.

Claims (1)

[Scope of utility model registration request] 1. A floor has a lower step portion extending substantially horizontally, a vertical wall portion extending upward from one end edge of the lower step portion, and a direction away from the lower step portion in plan view from an upper end edge of the vertical wall portion. A soundproof structure for an automobile floor, in which a heat-melting sheet is welded to the surface of the floor so that the joint between the lower step and the vertical wall extends substantially horizontally. In the above, the heat-melting sheet is a lower sheet welded to the surface of the lower step portion, a vertical wall sheet welded to the surface of the vertical wall portion, and straddles each surface of the vertical wall sheet and the upper step portion. A welded upper sheet is provided, and each edge of the lower sheet and the vertical wall sheet on the joint side is separated from each other with the joint sandwiched therebetween and is substantially parallel to each other along the joint. Soundproof structure for automobile floor .